Cordless electric shaver



May 15, 1962 A. H. KENT 3,035,191

CORDLESS ELECTRIC SHAVER Filed Aug. 18, 1958 2 Sheets-Sheet 1 rfa/eA/fyrMay 15, 1962 A. H. KENT 3,035,191

CORDLESS ELECTRIC SHAVER Filed Aug. 18, 1958 2 Sheets-Sheet 2 INVENTOR,ALLE/v A. Aff/vr- @Zag/ ning current reduces commutating problems.

3,035,191 CRDLESS ELECTRIC SHAVER Allen H. Kent, 20 5th Ave., New York,N.Y. Filed Allg. 18, 1958, Ser. No. 755,698 9 Claims. (Cl. S10-Sil)'Dhis application is a continuation in part of my copending applicationSerial No. 700,789, tiled December 5, 1957, which has matured intoPatent No. 2,963,598, granted Dec. 6, 1960.

The instant invention relates generally to electric Shavers and moreparticularly to a driving means for the razor head comprising aminiature D.C. motor and power pack combination which may beconveniently grasped with one hand during operation.

Today considerable consumer demand is directed toward small power drivendevices, Therefore, it is highly desirable to utilize a driving meanswhich includes its own source of power. Heretofore, efforts along theselines have produced driving means of considerable bulk and/or weightwhich, if directly coupled to the device in question, would make thehand manipulation of the device with any degree of precision animpossible task.

The instant invention provides a hand holdable driving means includingits own power source adapted especially for a razor head. In essence, mydriving means comprises a power pack :and a miniature D.C. motor of thetype described in my copending application 683,641, tiled September l2,1957. The power pack includes a holder wherein a plurality of circularlyarranged miniature cells, such as 1.5 volt dry cell manufactured by theBurgess Battery Co. and designated 9K, are operatively disposed.

The power pack holder is of a frame-like construction comprising twoinsulating end disks maintained in spaced relationship by a plurality ofelongated conducting struts ofk V-shaped cross-section to providerigidity. A first contact member extends laterally in,` a rst directionfrom one endof each of the struts while a second contact member extendslaterally in a second direction, opposite to the irst direction, fromthe other end of the strut. With this construction the cells areautomatically con- 'nected in series by merely inserting all of thecells into the holder with the positive terminals facing in the samedirection. Thus the conducting struts serve the dual functions of beingsupport members and being circuit connectors.

This holder construction makes it highly unlikely that even an unskilledperson will insert the cells in bucking relationship. The seriesconnection of cells is preferred over a parallel connection since thehigher voltage obtained thereby permits a motor of the same physicalsize to develop a greater starting torque and the lower run- Further,connection resistances become less critical as the voltage is raised. yl y The D C. motor and power pack are in alignment with one off themotor terminals arranged,y direct Contact with one end of the seriesconnectionsvvofV the cells While a control means selectively engages;the motor casing which is connected to the other motor terminal, andwhen engaged completes the circuit to theI other end of the seriesconnection of cells. The control means comprises a simple resilientconducting stripslidably mounted in electrical contact to the strutbearingythe Yend terminal in the series connection and being selectivelypositionable to engage the otherV motor terminal.

The motor and power pack are secured to one anl.

other lby means of two long studs which extend through studs also securethe components of the motor in place.

3,035,191 Patented May 15, 1962 One of the motor end brackets is formedwith two integral bayonets. The bayonets are radially projected and aredisposed to be received by slots in the housing of the razor head tocooperate therewith in securing the head to the motor.

The motor shaft extends past the end bracket having the bayonets and isreceived by a central opening of the rotor whereon the blades aremounted. A compression spring, rigidly secured to the motor shaft,includes an axially extending end section engageable with the rotor forrotating the blade assembly. rFhis sarme spring also urges the bladesagainst the screened whisker guide.

Accordingly, a primary object of the instant invention is to provide anovel hand held driving means and razor head driven thereby.

Another object is to provide a novel, light-weight com pact combinationof a D.C. motor and a power pack.

Still another object is to provide a novel stud fastening means wherebythe motor and power pack are mechanically secured to one another incorrect angular relationship with the fastening means also securing themotor components in place.

A further object is to provide a novel power pack including a holderwherein a plurality of circularly arranged dry cells are automaticallyconnected in electrical series merely by inserting the cells with theterminals facing in the same direction. v

A still further object is to provide a frame-like holder comprising twoend disks maintained in spaced relationship by means of `a plurality ofconducting struts with the struts serving the dual functions of beingstructural members and conducting members.

Yet another object is to provide'a novel control means for the motorcomprising a resilient member slideably mounted to one of the conductingstruts off the holder.

Still another object is to provide a single spring means which serves asa driving connection between a motor and razor head and also biases theblades against the Whisker guide.

These as well as other objects of the instant invention shall becomereadily apparent after reading the following description of theaccompanying drawings in which:

FIGURE 1 is a partially sectioned side elevation of the electric razorof the instant invention.

FIGURE 2 is a partially sectioned side elevation of the razor of FIGURE1 with certain components re,- moved.

FIGURES 3-5 are cross-sections of FIGURE l taken through lines 3-3, 4-4,and 5-5, respectively, looking in the directions of the arrows.

FIGURE 6 is a cross-section taken through line 6 6 of FIGURE 2 lookingin the direction of arrows 6-6.

FIGURE 7 is a perspective View illustrating the mountingkof a strutbetween the two end disks of the power pac FIGURE 8 is a partiallysectioned side elevation of the housing of the razor head.

FIGURE 9 is an end view of the razor head looking in the direction ofarrows 9 9 of FIGURE 8.

FIGURE l() is an exploded view of the electric razor of FIGURE 1.

Referring to the figures, the device of the instant nvention includes adriving means which comprises power pack 21 completely disposed withincylindrical power pack housing 22 and miniature DC. motor 23 partiallyentered into housing 22. l VMotor 23 is of the type completely describedin my aforesaid copending application 683,641 and includes 'a'rmetallichousing section 24 disposed between insulating'rend bracket 25 andmetallic end bracket 26 with output shaft 27 extending outward throughend bracket 26.

End bracket 26 includes an integrally formed section 1, of a diametersmaller than the outer diameter of motor 23, having radially extendingbayonets 102 which are received 'by L`shaped openings 103 of razor headinsert 104 to secure razor head 7105 to motor l23.

Razor -head 105 includes a ring housing v1016 having a screen Whiskerguide '107 over one -end thereof.` Insert 104 is coaxially arrangedwithin housing 10 6-and`includes an internal annular groove whereinspring retainer 108 is disposed. Spring 103 Oloosely retainsk bladeassembly 110 within housing 106 between screen 107 and spring 108.

Blade assembly 110 comprises a rotor V1511 having three radially"extending arms 112 whereon 'blades 113 are secured fas by rivets 114.The Acutting Aedges `115 'of blades 113 are urged into lcontact withscreen 107 by compressionspring 116 which is rigidly secured at one endto motor shaft 27 and vbearing against rotor 111.v Longitudinallyextending .projection 118 at the free end of spring 1:16 'engages one ofthe rotor arms 112 along an edge thereof to provide a driving connectionbetween motor 23 and rotor 111. At this time the free end of motor shaft27 is disposed within the central opening 11111 of rotor 111. Y

' Terminal members 28 Aand 33 are disposed between end bracket 25' andinsulating retaining member 30. End '28a of terminal member 2S engages aspring 201 which biases one of the motor brushes 2012 while the otherend 2070 is disposed within slot 2.9 radially extending from central'opening l31 of member 30 within which bearing cup 32 is disposed. Oneend 33a of terminal member 33 engages another spring 203 which biasesthe other motor brush 204 while the other end 33b is disposed withinslot 30ar extending from the central opening 31 radially to the edge ofmember 30. End 3-3b is bent back on itself to form Vaterniinalengageable bythe cell casing which .forms the negative terminal'of drycell 35.

'Power pack 21 comprises four `dry Vcells 35-38 arranged circularlywithin holder 40 which includes top 41 'and bottom 42 insulating disks.-Four struts 43-46 which maintain insulating disks 41, "42 `in spacedparallel relationship, are circularly Varranged so that a cell 35438 mayfit between any two adjacent struts 43-46. l

Ea'ch strut 43-46 is an elongated member of V-s'haped cross-sectionhaving a pair of tabs 47, `48 at each end which, after being enteredthrough appropriate slits in 'disks 41, 42, are bent overthe outer faces-thereof to to the arithmetic sum of the voltages appearing across allof the cells 35-33.

Motor 23 is positioned in axial alignment with powerpack 21 at one endthereof land is angularly arranged so that motor -terminal member end336 is positioned Within radial slot 41a of disk "41 and will contactthe t negative terminal of cell 35. Studs 150, 151 and nuts sulatingmember 30,disk 41 and disk 42. The threaded ends of studs 150, 151 areengaged hy nuts :1:52, 153, respectively, while the head of studs 150,151 are disposed within countersunk holes `surrounding vthe aperturesthrough end bracket 26. Thus, studs 150, 151 notonly secure motor 23ftopower kpack 21 but also secure end .secure -struts 213-46 to disks 41,42. as a rigid structure. Y

Each strut /43-45 also'includes terminals 49, 50 formed integrallytherewith and positioned adjacent to the .inner faces of disks 41, 42,respectively. Terminal 49' extends 'at right angles, in a iirstdirection, from one leg of .the 'V 'while terminal '50 extends at rightangles, ina second, from the other leg ofthe V with the second direction"being substantially opposite to said iirst direction. Terminals 49, Y50are each appropriately bowed at 52 and y'53. The bowing yat 52 and 53together with the resiliency n of the "strut material assures goodelectrical contact beyelectrical path is established as follows: fromterminal v 50 .of s'trut 46, 'through cell 38 from plus to minus toterminal 49 of strut 45, through strut 4S to terminal 50lthereof,'through cell 37' from plus to minus Vto terminal '49 of strut44, through strut 44 ,to terminal 50i thereof, through cell :36 fromplus to minus to terminal 49 of jstr'u't 43, and finally ,through cell35 from plus to minus. Thus, the voltage between strut 46 and theterminal of cell 35 not connected to terminal 50 of strut 43 is equalbrackets 25, 26 to motor housing 24. It is to be noted that studs 150,15-1 are disposed between the arms of V-struts 4S, 43, respectively, soas not to interferewith the insertion and withdrawal of cells 35-38.

A control means for selectively energizing motor 23 comprisesV aresilient conduct-ing strip 60, the maj-orporf tion 61 off which is insliding contact with strut L46 being retained thereto lby tabs 62 bentinwardly `from the long edges of strut `46. Strip V60 is stepped'atyshoulder 63 to provide a portion 64 olset from portion 61. Plastictab 65 is secured by rivet 66 to the free end of oiiset portion 64.

When tab `65 is moved toward razor head 105 protrusion 68 of -oifsetportion 64 engages .motor terminal Ymember end 28a thereby connectingterminal member 2S Yto the position end of .the serially connected cells35-38 while the other motor terminal is connected 'to 'the negative endof cells 35-38 so that motor 23 is energized to rotate the blades 113clockwise with respect to FIG-V URE 10.

When tab '65 is moved toward the end of housing 22 closed by disk 67,protrusion 68 is moved clear of terminal member end A28a to interruptthe connection between the cells 35-3'8 and motor 23. Y t

.The sliding limits of resilient strip 60 are established at one end bythe engagement of shoulder 6-3 with disk`41and at the other end by theengagement of strip end -61a with disk 42. f

YWhen the motor23 power pack V2.1 Vcorribination is inserted intohousing 22 disk 42 of the power pack holder 40 is positioned oppositeinsulating closure disk 161 of housing 22. A resilient ring 98 ofslightly larger diameter vthan end bracket 25- is interposed betweenthis bracket and motor housing 24. Ring 98 is `provided with a slot 97for thepassage of offset portion 64. The .power .pack housing 22, nearthe open end thereof, is engaged by the outer edge'of ring 98 forclosure of `housing 22.

YAn L-shaped spring member 172 includes foot .1'73 having an openingthrough which stud 151 passes. Foot 173 is positioned between disks v41and .30 with leg 174 of member 1.72 extending toward head 104. Fiber.washer 175 is interposed between disks 41 and foot 173. Leg 174 bearsagainst the inside surface of housing 22 to retain housing .22fto theremaining elements.

Typically, driving means 10 is 3%/2 inches Vlongby 1`1/2 inches indiameter weighingless .than one half pound, with the motor 23 beingcapable of vdeliver-ing 0.4 voz./in. of torque to operate razorhead`105. Withrazorhead 105 `included the yunit is approximately 4% 'incheslong.

Thus, I 'have provided a self powered electric razor including manynovel construction features which lend themselves to'inexpensivefmassproduction techniques.

Although I have here described lpreferred embodiments of my novelinvention, many variations and .modifications will now be apparent'tothose skilled in the. art, and Iy therefore vprefer to be limited, not4by the speciic disclosure herein, but only by the appending claims.

I claim: I

'1. A driving means comprising a D.C. motor and a power pack in axialalignment with said motor and operatively 'connected thereto; said powerpack comprising a plurality of cells each having a positive and anegative terminal; said plurality of cells connected in series aidingrelationship to form a voltage source with all of said positiveterminals positioned in a first plane and all of said negative terminalsbeing positioned in a second plane; a holder wherein said plurality ofcells are disposed; said holder comprising a pair of insulating membersand a plurality of struts, having V-shaped cross-sections, equal innumber to the cells of said plurality of cells; said plurality of strutsproviding a structural support to maintain said pair of insulatingmembers in spaced relationship parallel to said first plane and alsoserving as electrica*L connectors between the cells of said plurality ofcells; said D.C. motor including a first and a second terminal member;said voltage source having a pair of terminals; said first terminalmember electrically connected lto one of said pair of terminals; acontrol means including a resilient member when in a first positionelectrically conneoting said second terminal member to the other of saidpair of terminals thereby causing rotation of said D.C. motor;saidresilient member slideably mounted to the other of said pair ofterminals; said D.C. motor also inoluding a pair of end brackets `atleast one of which comprises an insulating material; a stud meansextending through said pair of end brackets and said holder insulatingmembers to thereby maintain the elements of said motor in operatingposition and also secure said power pack to said motor.

2. Driving means for a device, such as a razor head, having a rotatableassembly; said driving means comprising a D.C. motor and a power packoperatively connected thereto for energization thereof; said motorhaving an output shaft positioned for entry into a central opening of anassembly whereby said shaft is coaxial with an axis of rotation of thatassembly; a coil spring rigidly secured at one end thereof to said shaftand operatively positioned to urge an `assembly axially with rmpect tosaid shaft away from said motor; said coil spring, at the other endthereof, having a projection extending axially with respect to saidshaft misaligned with said shaft, and removably engageable with theassembly for transmitting rotation of said shaft thereto; said motorincluding a first and a second end bracket at opposite ends thereof;said first lbracket: including a portion of reduced area having bayonetmeans projecting therefrom for engaging cooperating means of theassembly and removably securing same to said driving means; said portionof reduced area and said bayonet means constructed integrally with theremainder of said first bracket.

3. The driving means set forth in claim 2 in which the power pack ispositioned in axial alignment with said motor and being comprised of aplurality of cells each having a positive and a negative terminal; saidplurality of cells connected in series aiding relationship to form avoltage source with all of said positive terminals positioned in a firstplane and all of said negative terminals being positioned in a secondplane; a holder wherein said plurality of cells are disposed; saidholder comprising a pair of insulating members and a plurality of strutsequal in number to the cells of said plurality of cells; said pluralityof struts providing a structural support to maintain said pair ofinsulating members in spaced relationship parallel to said first planeand also serving as electrical connectors between the cells of saidplurality of cells.

4. Driving means lfor la device, such as a razor head, having arotatable assembly; said driving means comprising a D.C. motor and apower pack operatively connected thereto for energization thereof; saidmotor having an output shaft positioned for entry into a central openingof an assembly whereby said shaft is coaxial with an axis of rotation ofthat assembly; a coil spring rigidly secured to one end thereof to saidshaft and operatively positioned to urge an assembly'axially withrespect to said shaft `faway from said motor; said coil spring, at theother end thereof, having a projection extending axially with respect tosaid shaft misaligned with said shaft, and removably engageable with theassembly for transmitting rotation of said shaft thereto; said motorincluding a first and a second end bracket at opposite ends thereof;said first bracket including a portion of reduced area having bayonetmeans projecting therefrom for engaging cooperating means of theassembly and removably securing same to said driving means; said portionof reduced area and said bayonet means constructed integrally with theremainder of said first bracket; said power pack positioned in axialalignment with said motor and comprising a plurality of cells eachhaving a positive and a negative terminal; said plurality of cellsconnected in series aiding relationship to form a voltage source withall of said positive terminals positioned in a first plane and all ofsaid negative terminals being positioned in a second plane; a holderwherein said plurality of cells are disposed; said holder comprising apair of insulating members and a plurality of struts equal in number tothe cells of said plurality of cells; said plurality of struts providinga structural support to maintain said pair of insulating members inspaced relationship parallel to said first plane and also serving aselectrical connectors between the cells of said plurality of cells; acontrol means for selectively energizing said motor, comprising aresilient member slidably mounted to a first strut of said plurality ofstruts; said resilient member selectively operable into engagement witha rst terminal of said motor.

5. The driving means set forth in claim 4 in which the resilient memberincludes a shoulder cooperating with a first of said -pair of insulatingmembers and a second of said insulating members cooperating with a firstend of said resilient member to define limits of travel of saidresilient member with respect to said power pack.

6. The driving means set forth in claim 5 in which each strut of saidplurality of struts comprises an elongated member having a V-shapedcross section; each of said struts having a rst terminal formedintegrally therewith and extending from one end thereof at right anglesto one leg of the V in a first direction; all but said rst strut havinga second terminal formed integrally therewith and extending from theother end thereof at right angles to the other leg of said V in a seconddirection diverging from said first direction.

7. The driving means set forth in claim 4 also comprising a cylindricalhousing having an open first end; said power pack entered through saidrst end completely disposed within said housing; one of said endbrackets of said D.C. motor extending through said first end; one end ofsaid resilient member positioned externally of said cylindrical so as tobe accessible for manual operation.

8. Driving means for a device, such as a razor head, having a rotatableassembly; said driving means comprising a D.C. motor and a power packoperatively connected thereto for energization thereof; said motorhaving an output shaft positioned 'for entry into a central opening ofan assembly whereby said shaft is coaxial with an axis of rotation ofthat assembly; a coil spring rigidly secured at one end thereof to saidshaft and operatively positioned to urge an assembly axially withrespect to said shaft away from said motor; said coil spring, at theother end thereof, having a projection extending axially with respect tosaid shaft misaligned with said shaft, and removably engageable with theassembly for transmitting rotation of said shaft thereto; said motorincluding a first and a second end bracket at opposite ends thereof;said power pack positioned in axial alignment with said motor andcomprising a plurality of cells each having a positive and a negativeterminal; said plurality of cells connected in series aidingrelationship to form a voltage source with all of said positiveterminals positioned in a first plane and all of said negative terminalspositioned in a second piane; :a hoideffwherein said pluralityarcfensfarjedisf posed; said holder comprising 'af-pair of insulatingmembers and a pluralityof struts e'qual'in numbertothecells" astructural support tol maintain said pairof insulating members yinspacedyrelationship to said rst planeandyalso serving as electricalconnectors `lljetwee'n th'e'cells' of said pllralityof cells; ystudmeans extending vthrough said brackets and said-pair of insulatingmembersto secure said power' pack' to said motor' and to` maintainthe'ele' mentsof said motor in their operative positions.

9. Th'driving means set forth iriclaim 8'also` compris;y ing afcontrolmeans for 4selectively energizing said motor, l comprising meanslmounted to a first strut'fof pluralityof 'l .struts Vand beingselectivelyperablelinto engagement' 796,517- Jackson Aug..'8, 1905-2,449,568` 2,449,81r Y 2,773,306 A 8 Von Ohlsen May 1', {Flornian"Nov."20, Biniek May 12, Goldschmidt Aprl27,

'v Gruessn'er" Mai'. 7', Jackson Apr. 14,V Schaaf et a1'. Nov. 3;Richardson et yal. lian.Y 5, Olschewski Nov. 2, Shriot Sept.'2'1,Hartford Sept'. 21, Ranson Deck' 11, Eilenberger etal. Dec/25,Villeneuve V Oct.` v15,

FOREIGN PATENTS( France Sept. 3,

